Internal-combustion engines – High tension ignition system – Using capacitive storage and discharge for spark energy
Patent
1988-01-07
1988-11-22
Nelli, Raymond A.
Internal-combustion engines
High tension ignition system
Using capacitive storage and discharge for spark energy
123597, F02P 306
Patent
active
047857897
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
The present invention relates to a method and system for controlling the spark ignition of spark plugs, in the ignition system of a multi-cylinder four-stroke internal combustion engine.
The present invention has particular application for controlling the spark ignition in at least two cylinders of the foregoing type of engine, wherein the pistons of such cylinders simultaneously assume a top dead center position, and wherein an ignition capacitor operates in conjunction with at least two discharging circuits and one charging circuit. The discharging circuits each comprise, in series, a primary winding of an ignition coil and a first circuit breaker element which can be switched from an electric control unit. The charging circuit supplied with current from a direct-current source, comprises a coil in series with a second circuit breaker element which can be switched from the control unit.
An engine as specified above can comprise, for example, a four-cylinder Otto-cycle engine in which the electric control unit included in the ignition system replaces a conventional mechanically controlled ignition distributor. Some of the electric control unit lacks a cam shaft transmitter, it is not possible to initially determine which cylinder is the first one to be in firing position. To ensure that ignition voltage is generated in the cylinder which is in firing position, it is suggested to allow the control unit to trigger ignition at the same time in two or all cylinders as soon as the signal from a crank shaft transmitter indicates that the pistons in a pair of cylinders assume the top dead centre position. In this arrangement, the charge of the ignition capacitor is utilized for simultaneous ignition in two or more cylinders and, as a result, only half or less than half of the charge of the ignition capacitor is used for generating ignition sparks in a cylinder.
If the voltage of the direct-current source drops due, for example, to low environmental temperatures, special starting problems occur with engines of the type just described. Thus, a low source voltage can result in the control unit not being able to properly control the charging processes occurring during a starting procedure.
Through German Patent Specification No. 2 448 302, a method and system are already known for assuring, during the start of an internal combustion engine, the charging of an ignition capacitor even with a decreasing battery voltage. But this does not teach how to arrange the charging and discharging of the ignition capacitor to obtain a more reliable ignition when starting an engine of the type as specified above.
SUMMARY AND OBJECTS OF THE INVENTION
A principal object of the present invention is to provide a method and system for obtaining a more reliable ignition for the type of engine specified above.
In achieving the foregoing object, the invention provides that when the pistons of the above-mentioned cylinders pass through the same crankshaft angle range close to the top dead centre position, a control unit emits first through fourth signals. The first signal is to the circuit breaker element of a first discharging circuit for triggering ignition in one of the above-mentioned cylinders. The second signal is to the second circuit breaker element for starting current supply to a charging circuit, which may include a coil. The third signal is also to the second circuit breaker element for interrupting current supply to the charging circuit, the ignition capacitor being charged with the energy stored in the coil. The fourth signal is to the circuit breaker element of a second discharging circuit for triggering ignition in the second one of the above-mentioned cylinders. Between the second and third signals the charging circuit is energized for a first time period, and between the respective ignitions of the first and fourth signals there runs a second time period which exceeds the first time period.
By means of the invention the ignition voltage can thus be generated for the cylinder pair in such a
REFERENCES:
patent: 4245609 (1981-01-01), Garry
patent: 4273093 (1981-01-01), Ozawa
patent: 4445491 (1984-05-01), Ishikawa et al.
patent: 4462363 (1984-07-01), Nanjyo et al.
patent: 4515140 (1985-05-01), Enomoto et al.
patent: 4610237 (1986-04-01), Ionesca et al.
patent: 4633834 (1987-01-01), Takeuchi et al.
patent: 4672941 (1987-06-01), Yamagata
Johansson Hans
Nytomt Jan
Nelli Raymond A.
Saab-Scania Aktiebolag
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